Nonmetallic gear



1 1927. Oct E. J. GUAY ET AL NONMETALLIC GEAR Filed Jan. 1926 #0 0 W rn. t

e e t vi A sectional view of a portion of a finished Patented Oct. 18,1927.

UNITED STATES 1,646,242 PATENT OFFICE.

EMILE J. GUAY, OF SWAMPSCOTT, AND CLARENCE W. MANSUR, F MALDEN, MASSA-CHUSETTS, ASSIGNOBS T0 GENERAL ELECTRIC COMPANY, A CORPORATION OF NEWYORK.

NONMETALLIC GEAR.

Our invention has for its object to improve the construction of gearsand gear material of the above-mentioned type and also to reduce thelosses due to wastage of valuable materials.

For a consideration of what We believe to be novel and our invention,attention is directed to the accompanying description and the claimsappended thereto.

In the drawing which is illustrative of our invention, Fig. 1 is a sideview of a rim or a rim member of a gear blank; Flg. 2 1s a sectionalview showing how the fabric ribbon is pleated in a plane perpendiculartothe axis of the blank; Fig. 3 is aside View on a somewhat enlarged scalealso showing the arrangement of the pleats; Fig.4: is a cross section ofa rim member; Fig. 5 is a gear, and Fig. 6 shows a'folded over ribbon tocompensate for variations in thickness of the inner and outer edges ofthe rim members.

so a

In carrying out our invention, we employ a relatively narrow ribbon 7for forming a.

large portion of the rim. The ribbon may be woven as such, or it may bemade by cutting a Wide sheet into strips. The latter method has someadvantages over the former due to the fact that it is more nearlyuniform in thickness due to the absence of tlIu; such a ribbon is woundon edge to form an annulus it will be found that the inner edge will becrim'pedwhile the outer edge is tight. This is due to the fact thatwhereasthe diameters of the inner and outer. edges are differenttheamount of fabric or numbers of threads at said ed es is the same. Tocompensate for this ifi'erence of diameter we closely pleat the ribbon,the depth of the threads which form the selvage edge. 40

pleats being governed by the diameter of.

the blank and the width of the ribbon; To attain the best results thepleats are deeper at the inner edge than at the outer, the amount beinggoverned by the difference of diameter of the two, edges. If the pleats9, 1926. Serial No. 80,216.

are made uniform the desired result may be obtained by having the pleatsoverlap at the inner edge. The ribbon may be coated with a binder suchas a phenolic condensation product, either before or after pleating, but

as a general thing it is preferable to first coat the ribbon and thenpleat it, since by so doing an excess of binder is avoided, it beingremembered that the strength and elasticity of the finished product isdue to the woven fabric and not to the binder. The

ribbon after being coated with the binder,

and dried in any suitable way, is closely pleated, as indicated at 8 inFig. 2. In this figure the portions of the pleats are, purposelyseparated so that the arrangement can be clearly seen. It will be notedthat'by thispleating each layer of the ribbon as ap-- plied to the rimmember comprises three thicknesses of fabric. The ribbon should beclosely pleated so as to avoid the formation of pockets containingbinder alone as. distinguished from fibers and a binder in the finishedproduct. After the ribbon is pleated it is wound edgewise around a drumor equivalent support to form a helix such as indicated in Fig. 1, theplane of each turn of the helix and hence .of the pl'eatsthemselvesbeing perpendicular to the axis thereof. This perpendicular arrangementis important because when the teeth are cut in the blank the edges ofthe numerous la ers,

as distinguished from the side face 0 the fabric, will be presented tothe teeth of the companion meshing gear. For gears intended forrelatively heavy duty, it is preferable to make the pleats slightlydeeper at the inner edge than at the outer edge, as indicated by thedotted lines 9 in Fig. 3, or if the pleats be uniform to overlap them atthe inner edge. The purpose of this is to avoid as far as possible openspaces or pockets between adjacent pleats in the same turn of thehelix.If there are such spaces or pockets the will be filled with binder inthe heating an pressing operations and for some classes of gears this isnot particularly objectionable but for heavy duty gears it is desirableto have fibers of the fabric as uniformly arranged as possible and toavoid even very The helix should be so woundthat the bends dueto thespreading of the fibers of which the fabric is composed when'subjectedto the heavy pressure usedin the final operation.

of the pleats in the difi'erent'layers, turns, or-laminations do notregister, i. e., a pear in the same axial plane, but should e .in stagered or overlapping relation- In other wor s, the bends in-one turn'ofthe helix should be opposite the first surface of the adjacent turns ofpleated ribbon. To accomplish this, the pitch of the pleats should besuchthat a given number of pleats will cover a little more or a littleless than the complete circumference of the drum used in the formingoperation. The non-register ing arrangement of the pleats is indicatedin Fig. 1 where the full lines 10' indicate the bends in the pleats ofone layer or turn, and the dotted lines 12 the bends inanother I layer.

It will be evident in using a ribbon of, uniform widthand thickness thatwhen Wound .into'a helix thesame number of fibers will be present at theinner as well as the outer diameter of the ring or turn of the helix andbecause the diameter at the periphery is greater than at the innersurface or bore of the ring or turn the material in the region ofthebore will be slightly thicker, measured -axia-lly, than in the region ofthe periphery.

In some gears this does not make any difl'erence but in others it does.Where it is de- "sired to make a rim" of uniform thickness anddensity offibers, inserts maybe em vployed and preferab1y* made from woven 1fabric, although other materials having suit able characteristics may beused. In Fig.

- tween rim members, between parts of a memthe members.

= pieces of woven ber, or they may be applied to the sides of Thehelically wound rim member may be applied directly to a metal center orto a center composed of textile binder-treated material. Thelatter maybe composed of fabric, or moldable materials,-or a combination of both.In Fig. 5

15 shown a center or webx15 composed of binder-treated wovenfabric madein the formof disks, se ments or' other forms. Preferably, someo thedisks 16 -will extend from between thev rings or rim members to the hubthus tying them to the hub elements while'others .will serve to -coverthe sidefaces of therim members andialso-to tie them to,

the web and hub. The web maybe keyed directly to thesupporting shaft ora metal hub such as 17 may be employed.

We have found that bodies made of pleated fabric and held undercompression by a suitable binder'are' muchharder to split inthe plane ofthe laminations than "when made of plain flatpieces piled fiatwise. 'Weattribute this chiefly to the fact that the adjacent surfaces consideredas a whole are not so smooth and uniform as is, the case with plain,flat pieces, and hence the binder tions. There is also a certaininterlocking of the laminations which further resists-the tendency tosplit. A' blank constructed as described has the great advantage thatthe more securely unites or bonds the laminathreads or fibers, eitherthejwarp orwoof in the rim are substantially parallel to-each [otherand. in planes perpendicular to the axis and hence a largepercenta ge ofthem extend radially'of the finished-teeth from the root to thepointthereof. i

It '.will be evident by utilizing ribbons as distinguished from disks,segments or other out forms, that a "cry great saving is effected in thehigh grade, expensive materials emareused for anchoring purposes or asfillers, any tr1mm1ngs or scraps resulting-from the cutting operatlonsmay be utilized in the 'webor hub portion of the'blank.

ployed. -When woven fabric disks or pieces After the parts have beenprepared as re-i I viously described, they are sub ected to eat tosoften the binderand then to ressure to compress the fibers,'the finalactlon of heat and pressure causing the binder to harden and retainthefibers in their compressed state thereby forming a uniformly ri 'idstructure. In this particular we may 01- low the established practice.-In forming gearblanks it ispreferable to employ molds of a single pieceof ribbon but in somencases .it will be satisfactory to use several suchiameter. I y 'Insteadof makmgfthe center portion, i. e. the hub andv webof woven fabric we may ieces, especially when the gear is of large makeit of a moldablecomposition compris- .ing textile material fibersand ahinder or othenucomp'ositionin fact which Will of an aiford a firmsupportfor. the rim and which will readily unite therewith whensubjected shaped to conform to the finished blanks. f Preferably eachrim member or unit is made to the temperaturesand. pressures used informing said IlIIl. "Where-such a composition center is provided itmaybe covered on.

both sides withv sheets of fabric which not only increases the strengthof the blank but im roves .its appearance.

at we claim as new and desire to secure by Letters Patent of the UnitedStates 1. Ablank of the; character described. hav

ing at least a portion of its rim comprising woven fabric arranged inlayers, said fabric being pleated, the pleats increasing in depth fromthe periphery inwardly, inserts which compensate for difference inthickness of different parts of the rim due to the form of the pleats,and a binder which holds the fabric in a compressed state.

2. A blank of the character described comprisin a hub portion, fabricdisks which extend from the hub portion to the periphcry of the blank,bodies of fabric located between the disks and forming with them therim, each of said bodies comprising layers of fabric which are pleatedover their entire surface, the pleats contacting with one another, theside pleats also contacting with the disks, and a'binder which holds thedisks and bodies in a rigid structure.

3. A blank of the character described comprising rings which form themajor portion of the rim and which are composedof relatively narrowstrips of woven and pleated fabric, said strips standing e'dgewise withrespect to the web of the blank with the pleats perpendicular to theaxis and in firm contact with one another, a woven fabric disk locatedbetween the rings and extending into the web to form an anchor, other.

anchoring, disks which form the side faces of the blank including theweb, and extend to the hub thereof, a fabric filling for the spacedefined by the outside disks, rim and hub, and a'binder which unites thevarious parts over their entire surface and holds the fibers thereof ina compressed state to form a rigid structure.

In witness whereof, we have hereunto set our hands this 7th day ofJanuary, 1926.

EMILE J. GUAY. CLARENCE w. mason.

